Several types of medical devices require long-term transdermal communication between the internal and external portions of the device. Examples of such devices include arteriovenous shunts, left ventricular assist devices, tissue expanders, and gastric lap bands. The transdermal portion of the device can be in the form of a catheter, a gas insufflation tube, or an electrical wire. These types of transdermal medical devices (hereinafter “TMDs”) are susceptible to infection.
For example, a laparoscopic adjustable gastric band (hereinafter “LAGB”) is an inflatable device that is placed around the top portion of the stomach via laparoscopic surgery and is often used to treat obesity. Most LAGBs have three portions including: (1) a gastric band; (2) an access (or injection) port; and (3) a connection tube, which allows for fluidic communication between the access port and the gastric band.
In a surgical procedure, the LAGB is placed around the upper part of the stomach, creating a small pouch that can hold only a small amount of food. The narrowed opening between the stomach pouch and the rest of the stomach controls how quickly food passes from the pouch to the lower part of the stomach. Depending on the patient's needs, after the device is implanted the narrowed opening between the pouch and the lower part of the stomach can be adjusted in size by inflating or deflating the gastric band portion. Inflating the band makes the opening smaller, causing food to pass more slowly. Deflating the band makes it wider, causes food to pass more quickly.
The adjustment is made by adding or removing fluid inside the hollow gastric band portion, by injecting or removing the fluid through the access port. This access port is placed under the skin in a muscle in the chest wall. As such, the port area is in transdermal communication with an outside environment and may be susceptible to infection.
There remains a need to reduce the incidence of infection associated with TMDs.